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Aberax Grand Master

Aberax

Posted
Posted
I don't know why people say that a RB25 with a RB26 crank/rods will make a RB27 because it won't.

RB25/26/30's all have the same bore 86mm so the only difference between the engines is the stroke. So guess what, if you fit a RB26 cranks in a RB25 you end up with an RB26 because the bore and stroke is the same as an RB26.

I believe to make a RB27 out of a RB25 you also need to do a 2mm bore as well so you get the extra displacement. I am not too sure, as finding info on this is near impossible for me, whenever i really search its pretty much about the Jun or Tomei stoker kits.

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Ryanrb25
Ryanrb25

i went for a hills run last night in the 31 with the roads very slippery.....was much fun. Had to bed in the bottom end bearings so yea..took it for a strap.

DSTROY
DSTROY

Hey Ryan, do you know how to fit a set of drop spindles to the front of a hilux???

Madaz
Madaz

Dam straight Damo would rather do SAU them heroin gts4 are 4.1 because they share the same parts from the gtr i think r32 gtst is 4.3 because of the lack of torque from the rb20

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DSTROY Grand Master

DSTROY

Posted
Posted
Your car is hot.

Cheers mate :(

yeah ive been in a 300rwkw car and loved every minute of it. was an amazing feeling :)

nice plates btw :)

Good stuff, i just wanted to know if you knew what sort of power you would be getting yourself into. Even 300kw in a rwd car is wheel spin city, 500rwkw would just be pointless i recon.

Madaz Grand Master

Madaz

Posted
Posted
I don't know why people say that a RB25 with a RB26 crank/rods will make a RB27 because it won't.

RB25/26/30's all have the same bore 86mm so the only difference between the engines is the stroke. So guess what, if you fit a RB26 cranks in a RB25 you end up with an RB26 because the bore and stroke is the same as an RB26.

wrong the stroke has to be longer since the bore is the same its the only way to change the capacity

Why don't you do what a bloke in the States did with TE27 and fit a 1UZ-fe, I'd say that you'd be the only person in Australia with a V8 keto. Having said that the CA would still make more power.

i believe there is another guy's that have done it

MissR34 Grand Master

MissR34

Posted
Posted
Good stuff, i just wanted to know if you knew what sort of power you would be getting yourself into. Even 300kw in a rwd car is wheel spin city, 500rwkw would just be pointless i recon.

oh yeah but even once the car is making 500rwkw will be dyno queen i think

but then i could be happy with 300rwkw

i wont know till im there really :(

D_Stirls Veteran

D_Stirls

Posted
Posted (edited)
wrong the stroke has to be longer since the bore is the same its the only way to change the capacity

Good to see we're on the same page because that's what i said. If you fit an RB26 crank in to a RB25 block you end up with a RB26, because the bore and stroke will then be the same as an RB26.

Edited by D_Stirls
DSTROY Grand Master

DSTROY

Posted
Posted
oh yeah but even once the car is making 500rwkw will be dyno queen i think

but then i could be happy with 300rwkw

i wont know till im there really :(

If i was to built a dyno car it would have to make 1000hp minimum.

SLED Grand Master

SLED

Posted
Posted

problem is, 500rwk from a 2.5 litre (turbo) will be totally gutless on the street and a stock standard RB25 will blow you away at the lights

It'll be an absolute pig to drive around town and will be gutless up until 5000rpm........from there it's wheel spin city all the way to 9000rpm and lots of broken bits to sweep up behind you unfortunately

D_Stirls Veteran

D_Stirls

Posted
Posted (edited)
it would be RB25/30

and ive been told that having the RB30 bottom end will help a lot with torque?

The way in which you will have to set up your head to get 1000rwhp means that you will lose all of the bottom end torque that you will have gained by fitting a 3 litre. having said that you will have more than a 2.5 litre.

I think you need to have a good look at what you want from this build and then going for broke because you can't have your cake and eat it too. If you want low down torque go back to looking at a Supercharger as there are S/Chargers that will make 1000hp. Or better yet look at fitting a VH45DE with a charger or twin turbos.

Either way once you start you'd better have some money behind you because building a 1000hp engine won't give you much if any change out of $40,000.

Edited by D_Stirls
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